Page:Popular Science Monthly Volume 19.djvu/839

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As further evidence that these insects well understand the advantages arising from the division of labor, I may quote one or two other observations. Thus Moggridge once saw a dead grasshopper carried into a nest of harvesting ants by the following means:

It was too large to pass through the door, so they tried to dismember it. Failing in this, several ants drew the wings and legs as far back as possible, while others gnawed through the muscles where the strain was greatest. They succeeded at last in pulling it in.

Again, Lespis says of the harvesting ant that,

if the road from the place where they are gathering their harvest to the nest is very long, they make regular depots for their provisions under large leaves, stones, or other suitable places, and let certain workers have the duty of carrying them from depot to depot.

No less, therefore, than the leaf-cutting ants already described, do these harvesting ants appreciate the benefits arising from the division of labor; and, as we shall presently see, there is a kind of ant exhibiting widely different habits, which shows appreciation of this principle in an even higher degree.

When the grain is taken into their nest by the harvesters, it is stored in regular granaries, but not until it has been denuded of its "husks" or "chaff." The denuding process, which corresponds to thrashing, is carried on below-ground, and the chaff is brought up to the surface, where it is laid in heaps to be blown away by the wind. It is not yet understood why the seed, when thus stored in subterranean chambers just far enough below the surface to favor germination, does not germinate. Moggridge proved that the vitality of the seeds is not impaired, for he grew some plants from seeds taken from the granaries; and he also found that the seeds would germinate even in the granaries, if the ants were prevented from obtaining access to them for two or three days. The non-germination of the seeds must, therefore, be due to some influence exerted by the ants. Moggridge thought this influence might be the exhalations from the ants, and so tried inclosing some seeds in a bottled test-tube, containing also earth and ants. The seeds, however, sprouted; and even an atmosphere of formic-acid vapor was found not to prevent germination. Probably, therefore, the ants in their granaries do something to the seeds for the express purpose of preventing germination; and, if so, it would be interesting to botanists to ascertain what this process can be.

But, be this as it may, there is no doubt that the ants are fully aware of the importance in this connection of keeping their garnered seeds as dry as possible; for when the latter prove over-moist after collection, or have been subsequently wetted by soaking rains, the insects bring them up to the surface and spread them out to dry, to be again brought into the nest after a sufficient exposure.

Lastly, Moggridge observed that the process, whatever it is, where-